Acid-resistant cable and preparation method thereof

Abstract

The invention discloses an acid-resistant cable and a preparation method thereof, and relates to the technical field of power cables. The acid-resistant cable prepared by the invention comprises a conductor, an inner insulating layer and an outer insulating layer, wherein the conductor is a copper conductor, the inner insulating layer is made of EPDM rubber mixed with modified carbon black, and the outer insulating layer is amide nitrile rubber; the modified carbon black is prepared by introducing calcium alginate on the surface of the carbon black after surface oxidation and freeze drying, and depositing calcium alginate aerogel on the surface of the carbon black; when preparing the amide nitrile rubber, the nitrile rubber is first epoxidized, then hydrogenated, and finally mixed with azido methane; the acid-resistant cable prepared by the application has excellent wear resistance and heat resistance, and good tensile strength.

Description

Technical Field

[0001] The invention relates to the technical field of power cables, in particular to an acid-resistant cable and a preparation method thereof. Background Art

[0002] As we all know, cables are the basis of data communication. Whether in the construction process or after commissioning, the power supply system is particularly important for power engineering, remote control, and construction engineering. Cables are the carriers of the power supply system. Strong current systems and weak current systems are controlled by power cables and control cables respectively. Cables are usually rope-like cables made of several or several groups of wires twisted together. Each group of wires is insulated from each other and often twisted around a center. The entire outer layer is covered with a highly insulating covering layer, which has the characteristics of internal power supply and external insulation.

[0003] Many fields require high-performance cables, and cables are often used in harsh working environments, especially in acidic and alkaline environments. Cables with EPDM rubber on the outer layer are often more acid-resistant, but less wear-resistant, heat-resistant and tensile-strength-resistant. Therefore, this application studies and prepares an acid-resistant cable with good wear resistance, heat resistance and tensile strength. Summary of the invention

[0004] The object of the present invention is to provide an acid-resistant cable and a preparation method thereof to solve the problems raised in the above background technology.

[0005] An acid-resistant cable mainly comprises the following raw material components in parts by weight: 40 to 80 parts of conductors, 3 to 5 parts of inner insulating layers, and 6 to 10 parts of outer insulating layers.

[0006] Preferably, the conductor is a copper conductor made by twisting single crystal copper wires.

[0007] Preferably, the inner insulating layer comprises EPDM rubber, modified carbon black and a rubber antioxidant; the modified carbon black is prepared by depositing calcium alginate aerogel on the surface of oxidized carbon black.

[0008] Preferably, the outer insulating layer comprises amide nitrile rubber, montmorillonite, polyamide and phosphite.

[0009] Preferably, the amide nitrile rubber is prepared by first epoxidizing nitrile rubber, then hydrogenating it, and finally blending it with azidomethane.

[0010] Preferably, a method for preparing an acid-resistant cable is provided, wherein the method for preparing an acid-resistant cable comprises: preparing a conductor, preparing an inner insulating layer, preparing an outer insulating layer, and preparing an acid-resistant cable.

[0011] Preferably, the method for preparing the acid-resistant cable comprises the following specific steps:

[0012] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0013] (2) The oxidized carbon black and sodium alginate are mixed in a mass ratio of 3:1 to 3.5:1, dispersed in ultrapure water 5 to 8 times the mass of the carbon black, heated to 70 to 80°C at 800 to 1200 rpm, and sulfuric acid with a mass fraction of 98% at a mass fraction of 0.04 to 0.08 times the mass of the carbon black is added, and the reaction is continued for 6 to 8 hours with stirring, and then cooled to room temperature, and a calcium chloride solution with a mass fraction of 5% at a mass fraction of 0.15 to 0.2 times the mass of the carbon black is added at a rate of 10 to 20 drops / min, and then a 5% ethylenediamine solution with a mass fraction of 0.2 to 0.3 times the mass of the carbon black is added, and the stirring is continued for 1 to 2 hours, filtered and washed with ultrapure water for 5 to 8 times, transferred to a low-temperature refrigerator and frozen at -80°C for 4 hours, and then quickly transferred to a freeze dryer and dried at -50°C and 10Pa for 8 hours to obtain modified carbon black;

[0014] (3) Mixing modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3 to 20:80:5, placing them in a heating extruder, heating them to a molten state, and continuously extruding them on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0015] (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine in an amount of 3 to 5 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution in an amount of 0.3 to 0.5 times the mass of the nitrile rubber, heating the mixture in a water bath to 70 to 80° C., adding hydrogen peroxide in an amount of 0.1 to 0.18 times the mass of the nitrile rubber at a rate of 15 to 20 drops / min, reacting for 1 to 2 hours, transferring the mixture to a reactor, adding rhodium chloride in an amount of 0.05 to 0.08 times the mass of the nitrile rubber, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing the mixture with anhydrous ethanol, placing the mixture in a vacuum drying oven, and drying the mixture at 60 to 80° C. for 1.5 hours, thereby obtaining epoxy hydrogenated nitrile rubber;

[0016] (5) dispersing the epoxy hydrogenated nitrile rubber in a 25% triphenylphosphine benzene solution having a mass fraction of 3 to 5 times the mass of the epoxy hydrogenated nitrile rubber, adding 0.2 to 0.3 times the mass of the epoxy hydrogenated nitrile rubber, heating to 80 to 90° C., standing and keeping warm for 0.5 to 1 hour, heating to 120 to 130° C., continuing to react for 20 to 30 minutes, condensing with anhydrous ethanol, and placing in a vacuum drying oven at 60 to 80° C. for 1.5 hours to obtain amide nitrile rubber;

[0017] (6) A mixture of amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 40:10:8:0.2 to 45:15:12:0.3 is placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to produce an acid-resistant cable.

[0018] Preferably, in the above step (2), the process of oxidizing carbon black is as follows: mixing carbon black with 98% nitric acid with a mass fraction of 6 times the mass of carbon black, stirring at room temperature and 800-1200 rpm for 30 min, heating in an oil bath to 150-180° C., keeping warm for 6-8 h, cooling to room temperature, filtering and washing with deionized water until the washing liquid is neutral, and finally drying in a drying oven at 75° C. for 3 h.

[0019] Preferably, in the above step (3): the thickness of the inner insulating layer is 0.03 to 0.05 mm.

[0020] Preferably, in the above step (6): the thickness of the outer insulating layer is 0.06 to 0.1 mm.

[0021] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0022] The acid-resistant cable prepared by the present invention comprises a conductor, an inner insulating layer and an outer insulating layer, wherein the conductor is a copper conductor, the inner insulating layer is made of EPDM rubber blended with modified carbon black, and the outer insulating layer is amide nitrile rubber;

[0023] The modified carbon black is prepared by introducing calcium alginate on the surface of the carbon black after surface oxidation and freeze drying, and depositing calcium alginate aerogel on the surface of the carbon black; carboxyl groups and hydroxyl groups are introduced on the surface of the surface oxidized carbon black, which react with the carboxyl groups and hydroxyl groups on the surface of sodium alginate to produce crosslinking, and then crosslink with calcium chloride to form calcium alginate, and finally crosslink with ethylenediamine to strengthen the structure of the aerogel and reduce the polar groups on the surface of the carbon black; when blended with ethylene propylene rubber, a crosslinking structure is formed with the lactone group and quinone group on the surface of the carbon black, and at the same time, the ethylene propylene rubber is adsorbed on the surface of the aerogel to enhance the The high cross-linking density enhances the bonding force with the modified carbon black and the wear resistance of the inner insulation layer. At the same time, the dispersion stability and compatibility of the modified carbon black in EPDM rubber are enhanced due to the reduction of polar groups. The thermal conductivity of the calcium alginate aerogel between the carbon black and EPDM rubber is low, which enhances the heat resistance of the inner insulation layer. When the inner insulation layer and the outer insulation layer of the cable are damaged at the same time, they are corroded by acid. The copper ions generated by the heat reaction between the conductor and the acid are instantly adsorbed into the aerogel and separated from the conductor, which speeds up the disconnection rate of the conductor and ensures the safety of personnel.

[0024] When preparing amide nitrile rubber, the nitrile rubber is first epoxidized, then hydrogenated, and finally blended with azido methane; the intermolecular force of the epoxidized nitrile rubber is increased, and it has strong adhesion. After hydrogenation, the aging resistance of the nitrile rubber is improved. When blended with azido methane and heated, azido methane generates nitre, which is inserted into the carbon-hydrogen bond of the nitrile rubber to form amide, thereby enhancing the crosslinking density of the nitrile rubber, and then enhancing the adhesion between the amide nitrile rubber of the outer insulating layer and the inner insulating layer; at the same time, the amide will also react with the hydroxyl and carboxyl groups on the modified carbon black in the inner insulating layer to tightly connect the inner and outer insulating layers, thereby enhancing the tensile strength of the cable. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the various index testing methods of the acid-resistant cables prepared in the examples and comparative examples as follows:

[0027] Heat resistance: The acid-resistant cables prepared in the examples and comparative examples were subjected to limiting oxygen index test according to GB / T2406.

[0028] Wear resistance: The acid-resistant cables prepared in the examples and comparative examples were tested for wear rate using a wear machine. The smaller the wear rate, the better the wear resistance.

[0029] Tensile strength: The acid-resistant cables prepared in the examples and comparative examples were subjected to a tensile strength test according to GB / T1040.

[0030] Example 1

[0031] An acid-resistant cable, measured by weight, mainly comprising:

[0032] 40 parts conductor, 3 parts inner insulation, 6 parts outer insulation.

[0033] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0034] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0035] (2) The oxidized carbon black and sodium alginate were mixed in a mass ratio of 3:1, dispersed in ultrapure water 5 times the mass of the carbon black, heated to 70°C at 800 rpm, and 98% sulfuric acid at a mass fraction of 0.04 times the mass of the carbon black was added. The reaction was continued with stirring for 6 hours, cooled to room temperature, and a 5% calcium chloride solution at a mass fraction of 0.15 times the mass of the carbon black was added at a rate of 10 drops / min, and then a 5% ethylenediamine solution at a mass fraction of 0.2 times the mass of the carbon black was added. The mixture was continued to be stirred for 1 hour, filtered and washed with ultrapure water 5 times, transferred to a low-temperature refrigerator and frozen at -80°C for 4 hours, and then quickly transferred to a freeze dryer and dried at -50°C and 10Pa for 8 hours to obtain modified carbon black;

[0036] (3) Mixing modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3, placing them in a heating extruder, heating them to a molten state, and continuously extruding them on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0037] (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine at a mass fraction of 3 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution at a mass fraction of 0.3 times the mass of the nitrile rubber, heating to 70° C. in a water bath, adding hydrogen peroxide at a rate of 15 drops / min at a mass fraction of 0.1 times the mass of the nitrile rubber, reacting for 1 hour, transferring to a reactor, adding rhodium chloride at a mass fraction of 0.05 times the mass of the nitrile rubber, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing with anhydrous ethanol, placing in a vacuum drying oven, and drying at 60° C. for 1.5 hours, epoxy hydrogenated nitrile rubber is obtained;

[0038] (5) dispersing the epoxy hydrogenated nitrile rubber in a 25% triphenylphosphine benzene solution having a mass fraction of 3 times the mass of the epoxy hydrogenated nitrile rubber, adding 0.2 times the mass of the epoxy hydrogenated nitrile rubber azido methane, heating to 80° C., standing and keeping the reaction for 0.5 h, heating to 120° C., continuing the reaction for 20 min, condensing with anhydrous ethanol, and placing in a vacuum drying oven, drying at 60° C. for 1.5 h to obtain amide nitrile rubber;

[0039] (6) A mixture of amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 40:10:8:0.2 is placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to produce an acid-resistant cable.

[0040] Preferably, in the above step (2): the process of oxidizing carbon black is: mixing carbon black with 98% nitric acid with a mass fraction of 6 times the mass of carbon black, stirring at room temperature and 800 rpm for 30 minutes, heating to 150°C in an oil bath, keeping warm for 6 hours, cooling to room temperature, filtering and washing with deionized water until the washing liquid is neutral, and finally placing in a drying oven at 75°C for 3 hours.

[0041] Preferably, in the above step (3): the thickness of the inner insulating layer is 0.03 mm.

[0042] Preferably, in the above step (6): the thickness of the outer insulation layer is 0.06 mm.

[0043] Example 2

[0044] An acid-resistant cable, measured by weight, mainly comprising:

[0045] 80 parts conductor, 5 parts inner insulation, 10 parts outer insulation.

[0046] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0047] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0048] (2) The oxidized carbon black and sodium alginate were mixed at a mass ratio of 3.5:1, dispersed in ultrapure water 8 times the mass of the carbon black, heated to 80°C with stirring at 1200 rpm, and sulfuric acid with a mass fraction of 98% at a mass fraction of 0.08 times the mass of the carbon black was added, and the reaction was continued with stirring for 8 hours, cooled to room temperature, and a calcium chloride solution with a mass fraction of 5% at a rate of 0.2 times the mass of the carbon black was added at a rate of 20 drops / min, and then a 5% ethylenediamine solution with a mass fraction of 0.3 times the mass of the carbon black was added, and the stirring was continued for 2 hours, filtered and washed with ultrapure water 8 times, transferred to a low-temperature refrigerator and frozen at -80°C for 4 hours, and then quickly transferred to a freeze dryer and dried at -50°C and 10Pa for 8 hours to obtain modified carbon black;

[0049] (3) Mixing modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 20:80:5, placing them in a heating extruder, heating them to a molten state, and continuously extruding them on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0050] (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine at a mass fraction of 5 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution at a mass fraction of 0.5 times the mass of the nitrile rubber, heating to 80° C. in a water bath, adding 0.18 times the mass of hydrogen peroxide of the nitrile rubber at a rate of 20 drops / min, reacting for 2 hours, transferring to a reactor, adding 0.08 times the mass of the nitrile rubber of rhodium chloride, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing with anhydrous ethanol, placing in a vacuum drying oven, and drying at 80° C. for 1.5 hours, to obtain epoxy hydrogenated nitrile rubber;

[0051] (5) dispersing the epoxy hydrogenated nitrile rubber in a benzene solution of triphenylphosphine in an amount of 25% by mass and 5 times the mass of the epoxy hydrogenated nitrile rubber, adding azido methane in an amount of 0.3 times the mass of the epoxy hydrogenated nitrile rubber, heating to 90° C., standing and keeping the reaction for 1 hour, heating to 130° C., continuing the reaction for 30 minutes, condensing with anhydrous ethanol, and placing in a vacuum drying oven, drying at 80° C. for 1.5 hours to obtain amide nitrile rubber;

[0052] (6) A mixture of amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 45:15:12:0.3 is placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to produce an acid-resistant cable.

[0053] Preferably, in the above step (1): the preparation method of polyamide is: dispersing ethylenediamine in methanol with a mass of 0.5 times that of ethylenediamine, stirring evenly in an ice bath to obtain solution A; dispersing methyl acrylate in methanol with a mass of 0.55 times that of methyl acrylate, mixing evenly to obtain solution B; adding solution B with a mass of 7.3 times that of solution A to solution A at a rate of 20 drops / min, then adding sodium ethoxide with a mass of 0.06 times that of ethylenediamine, adjusting the temperature to 35°C, stirring and keeping warm at 1200 rpm under a nitrogen atmosphere for 6 hours, transferring the reaction to a rotary evaporator after the reaction, and rotary evaporating at 40°C for 30 minutes to obtain polyamide.

[0054] Preferably, in the above step (2): the process of oxidizing carbon black is: mixing carbon black with 98% nitric acid with a mass fraction of 6 times the mass of carbon black, stirring at room temperature and 1200 rpm for 30 minutes, heating to 180°C in an oil bath, keeping warm for 8 hours, cooling to room temperature, filtering and washing with deionized water until the washing liquid is neutral, and finally placing in a drying oven at 75°C for 3 hours.

[0055] Preferably, in the above step (3): the thickness of the inner insulating layer is 0.05 mm.

[0056] Preferably, in the above step (6): the thickness of the outer insulation layer is 0.1 mm.

[0057] Comparative Example 1

[0058] An acid-resistant cable, measured by weight, mainly comprising:

[0059] 40 parts conductor, 3 parts inner insulation, 6 parts outer insulation.

[0060] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0061] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0062] (2) Mix carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3 and place in a heating extruder, heat to a molten state, and continuously extrude on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0063] (3) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine at a mass fraction of 3 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution at a mass fraction of 0.3 times the mass of the nitrile rubber, heating to 70° C. in a water bath, adding hydrogen peroxide at a rate of 15 drops / min at a mass fraction of 0.1 times the mass of the nitrile rubber, reacting for 1 hour, transferring to a reactor, adding rhodium chloride at a mass fraction of 0.05 times the mass of the nitrile rubber, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing with anhydrous ethanol, placing in a vacuum drying oven, and drying at 60° C. for 1.5 hours, epoxy hydrogenated nitrile rubber is obtained;

[0064] (4) dispersing the epoxy hydrogenated nitrile rubber in a 25% benzene solution of triphenylphosphine in an amount 3 times the mass of the epoxy hydrogenated nitrile rubber, adding 0.2 times the mass of the epoxy hydrogenated nitrile rubber of azido methane, heating to 80° C., standing and keeping the reaction for 0.5 h, heating to 120° C., continuing the reaction for 20 min, condensing with anhydrous ethanol, and placing in a vacuum drying oven at 60° C. for 1.5 h to obtain amide nitrile rubber;

[0065] (5) A mixture of amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 40:10:8:0.2 is placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to obtain an acid-resistant cable.

[0066] Preferably, in the above step (2): the thickness of the inner insulating layer is 0.03 mm.

[0067] Preferably, in the above step (5): the thickness of the outer insulation layer is 0.06 mm.

[0068] Comparative Example 2

[0069] An acid-resistant cable, measured by weight, mainly comprising:

[0070] 40 parts conductor, 3 parts inner insulation, 6 parts outer insulation.

[0071] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0072] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0073] (2) The oxidized carbon black and sodium alginate were mixed in a mass ratio of 3:1, dispersed in ultrapure water 5 times the mass of the carbon black, heated to 70°C at 800 rpm, and 98% sulfuric acid at a mass fraction of 0.04 times the mass of the carbon black was added. The reaction was continued with stirring for 6 hours, cooled to room temperature, and a 5% calcium chloride solution at a mass fraction of 0.15 times the mass of the carbon black was added at a rate of 10 drops / min, and then a 5% ethylenediamine solution at a mass fraction of 0.2 times the mass of the carbon black was added. The mixture was continued to be stirred for 1 hour, filtered and washed with ultrapure water 5 times, transferred to a low-temperature refrigerator and frozen at -80°C for 4 hours, and then quickly transferred to a freeze dryer and dried at -50°C and 10Pa for 8 hours to obtain modified carbon black;

[0074] (3) Mixing modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3, placing them in a heating extruder, heating them to a molten state, and continuously extruding them on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0075] (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine in an amount 3 times the mass of the nitrile rubber, adding 0.2 times the mass of azidomethane, heating to 80° C., standing for a 0.5 h heat preservation reaction, heating to 120° C., continuing the reaction for 20 min, condensing with anhydrous ethanol, and placing in a vacuum drying oven at 60° C. for 1.5 h to obtain amide nitrile rubber;

[0076] (5) A mixture of amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 40:10:8:0.2 is placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to obtain an acid-resistant cable.

[0077] Preferably, in the above step (2): the process of oxidizing carbon black is: mixing carbon black with 98% nitric acid with a mass fraction of 6 times the mass of carbon black, stirring at room temperature and 800 rpm for 30 minutes, heating to 150°C in an oil bath, keeping warm for 6 hours, cooling to room temperature, filtering and washing with deionized water until the washing liquid is neutral, and finally placing in a drying oven at 75°C for 3 hours.

[0078] Preferably, in the above step (3): the thickness of the inner insulating layer is 0.03 mm.

[0079] Preferably, in the above step (5): the thickness of the outer insulation layer is 0.06 mm.

[0080] Comparative Example 3

[0081] An acid-resistant cable, measured by weight, mainly comprising:

[0082] 40 parts conductor, 3 parts inner insulation, 6 parts outer insulation.

[0083] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0084] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0085] (2) The oxidized carbon black and sodium alginate were mixed in a mass ratio of 3:1, dispersed in ultrapure water 5 times the mass of the carbon black, heated to 70°C at 800 rpm, and 98% sulfuric acid at a mass fraction of 0.04 times the mass of the carbon black was added. The reaction was continued with stirring for 6 hours, cooled to room temperature, and a 5% calcium chloride solution at a mass fraction of 0.15 times the mass of the carbon black was added at a rate of 10 drops / min, and then a 5% ethylenediamine solution at a mass fraction of 0.2 times the mass of the carbon black was added. The mixture was continued to be stirred for 1 hour, filtered and washed with ultrapure water 5 times, transferred to a low-temperature refrigerator and frozen at -80°C for 4 hours, and then quickly transferred to a freeze dryer and dried at -50°C and 10Pa for 8 hours to obtain modified carbon black;

[0086] (3) Mixing modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3, placing them in a heating extruder, heating them to a molten state, and continuously extruding them on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0087] (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine at a mass fraction of 3 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution at a mass fraction of 0.3 times the mass of the nitrile rubber, heating to 70° C. in a water bath, adding hydrogen peroxide at a rate of 15 drops / min at a mass fraction of 0.1 times the mass of the nitrile rubber, reacting for 1 hour, transferring to a reactor, adding rhodium chloride at a mass fraction of 0.05 times the mass of the nitrile rubber, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing with anhydrous ethanol, placing in a vacuum drying oven, and drying at 60° C. for 1.5 hours, epoxy hydrogenated nitrile rubber is obtained;

[0088] (5) Epoxy hydrogenated nitrile rubber, montmorillonite, polyamide and phosphite are mixed in a mass ratio of 40:10:8:0.2 and placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to obtain an acid-resistant cable.

[0089] Preferably, in the above step (2): the process of oxidizing carbon black is: mixing carbon black with 98% nitric acid with a mass fraction of 6 times the mass of carbon black, stirring at room temperature and 800 rpm for 30 minutes, heating to 150°C in an oil bath, keeping warm for 6 hours, cooling to room temperature, filtering and washing with deionized water until the washing liquid is neutral, and finally placing in a drying oven at 75°C for 3 hours.

[0090] Preferably, in the above step (3): the thickness of the inner insulating layer is 0.03 mm.

[0091] Preferably, in the above step (5): the thickness of the outer insulation layer is 0.06 mm.

[0092] Comparative Example 4

[0093] An acid-resistant cable, measured by weight, mainly comprising:

[0094] 40 parts conductor, 3 parts inner insulation, 6 parts outer insulation.

[0095] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0096] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0097] (2) The oxidized carbon black and sodium alginate were mixed in a mass ratio of 3:1, dispersed in ultrapure water 5 times the mass of the carbon black, heated to 70°C at 800 rpm, and sulfuric acid with a mass fraction of 98% 0.04 times the mass of the carbon black was added, and the reaction was continued with stirring for 6 hours, cooled to room temperature, filtered and washed with ultrapure water 5 times, and dried in an oven at 80°C for 2 hours to obtain modified carbon black;

[0098] (3) Mixing modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3, placing them in a heating extruder, heating them to a molten state, and continuously extruding them on a conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0099] (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine at a mass fraction of 3 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution at a mass fraction of 0.3 times the mass of the nitrile rubber, heating to 70° C. in a water bath, adding hydrogen peroxide at a rate of 15 drops / min at a mass fraction of 0.1 times the mass of the nitrile rubber, reacting for 1 hour, transferring to a reactor, adding rhodium chloride at a mass fraction of 0.05 times the mass of the nitrile rubber, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing with anhydrous ethanol, placing in a vacuum drying oven, and drying at 60° C. for 1.5 hours, epoxy hydrogenated nitrile rubber is obtained;

[0100] (5) dispersing the epoxy hydrogenated nitrile rubber in a 25% triphenylphosphine benzene solution having a mass fraction of 3 times the mass of the epoxy hydrogenated nitrile rubber, adding 0.2 times the mass of the epoxy hydrogenated nitrile rubber azido methane, heating to 80° C., standing and keeping the reaction for 0.5 h, heating to 120° C., continuing the reaction for 20 min, condensing with anhydrous ethanol, and placing in a vacuum drying oven, drying at 60° C. for 1.5 h to obtain amide nitrile rubber;

[0101] (6) A mixture of amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 40:10:8:0.2 is placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to produce an acid-resistant cable.

[0102] Preferably, in the above step (2): the process of oxidizing carbon black is: mixing carbon black with 98% nitric acid with a mass fraction of 6 times the mass of carbon black, stirring at room temperature and 800 rpm for 30 minutes, heating to 150°C in an oil bath, keeping warm for 6 hours, cooling to room temperature, filtering and washing with deionized water until the washing liquid is neutral, and finally placing in a drying oven at 75°C for 3 hours.

[0103] Preferably, in the above step (3): the thickness of the inner insulating layer is 0.03 mm.

[0104] Preferably, in the above step (6): the thickness of the outer insulation layer is 0.06 mm.

[0105] Comparative Example 5

[0106] An acid-resistant cable, measured by weight, mainly comprising:

[0107] 40 parts conductor, 3 parts inner insulation, 6 parts outer insulation.

[0108] A method for preparing an acid-resistant cable, the method for preparing the acid-resistant cable comprising:

[0109] (1) placing single crystal copper wires into a stranding machine for stranding to obtain a copper conductor;

[0110] (2) EPDM rubber and rubber antioxidant are mixed in a mass ratio of 15:80:3 and placed in a heating extruder, heated to a molten state, and continuously extruded onto the conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer;

[0111] (3) Nitrile rubber, montmorillonite, polyamide and phosphite are mixed in a mass ratio of 40:10:8:0.2 and placed in a heating extruder, heated to a molten state, and continuously extruded onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to produce an acid-resistant cable.

[0112] Preferably, in the above step (2): the thickness of the inner insulating layer is 0.03 mm.

[0113] Preferably, in the above step (3): the thickness of the outer insulation layer is 0.06 mm.

[0114] Effect example

[0115] Table 1 below shows the performance analysis results of the acid-resistant cables using Examples 1 and 2 of the present invention and Comparative Examples 1, 2, 3, 4, and 5.

[0116] Table 1

[0117] Limiting oxygen index (%) Wear rate (%) Tensile strength MPa Example 1 38.9 2.1 18.7 Example 2 38.4 2.3 19.4 Comparative Example 1 25.4 4.4 18.8 Comparative Example 2 35.6 2.4 14.6 Comparative Example 3 36.7 2.3 13.4 Comparative Example 4 25.9 5.3 17.3 Comparative Example 5 23.6 5.6 11.5

[0118] By comparing the experimental data of the embodiments and the comparative examples in Table 1, it can be obviously found that the acid-resistant cables prepared in Examples 1 and 2 have good heat resistance, wear resistance and tensile strength; from the comparison of the experimental data of Example 1, Example 2 and Comparative Examples 1, 4 and 5, it can be found that when preparing modified carbon black, calcium alginate aerogel is deposited on the surface of oxidized carbon black, carboxyl groups and hydroxyl groups are introduced on the surface of the oxidized carbon black, and react with the carboxyl groups and hydroxyl groups on the surface of sodium alginate to produce crosslinking, and then the sodium alginate is converted into calcium alginate and made into aerogel, which can significantly enhance the heat resistance and wear resistance of the acid-resistant cable, while only using carbon black or in the carbon black The surface is connected with sodium alginate, and calcium alginate aerogel is not prepared, so the heat resistance and wear resistance of the cable cannot be enhanced. From the comparison of the experimental data of Example 1, Example 2 and Comparative Examples 2, 3, and 5, it can be found that epoxidation and hydrogenation are carried out when preparing the amide nitrile rubber to enhance the tensile strength of the acid-resistant cable, and after epoxidation and hydrogenation, the amide is blended with azidomethane to generate nitre, which is inserted into the carbon-hydrogen bond of the nitrile rubber to form amide, thereby enhancing the crosslinking density of the nitrile rubber. At the same time, the amide reacts with the hydroxyl and carboxyl groups on the modified carbon black in the inner insulating layer to tightly connect the inner and outer insulating layers, thereby enhancing the tensile strength of the cable.

[0119] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for preparing an acid-resistant cable, characterized in that: The following steps are involved: Conductor preparation, inner insulation layer preparation, outer insulation layer preparation, acid-resistant cable preparation; The preparation method comprises the following specific steps: (1) Putting single crystal copper wire into a stranding machine for stranding to obtain a copper conductor; (2) The oxidized carbon black and sodium alginate are mixed in a mass ratio of 3:1 to 3.5:1, dispersed in ultrapure water 5 to 8 times the mass of the carbon black, heated to 70 to 80°C at 800 to 1200 rpm, and sulfuric acid with a mass fraction of 98% at a mass fraction of 0.04 to 0.08 times the mass of the carbon black is added, and the reaction is continued with stirring for 6 to 8 hours, cooled to room temperature, and a 5% calcium chloride solution with a mass fraction of 0.15 to 0.2 times the mass of the carbon black is added at a rate of 10 to 20 drops / min, and then a 5% ethylenediamine solution with a mass fraction of 0.2 to 0.3 times the mass of the carbon black is added, and the stirring is continued for 1 to 2 hours, filtered and washed with ultrapure water for 5 to 8 times, transferred to a low-temperature refrigerator and frozen at -80°C for 4 hours, and then quickly transferred to a freeze dryer and dried at -50°C and 10Pa for 8 hours to obtain modified carbon black; (3) Mix the modified carbon black, EPDM rubber and rubber antioxidant in a mass ratio of 15:80:3 to 20:80:5 and place them in a heating extruder, heat them to a molten state, and continuously extrude them onto the conductor under the action of a forming die and extrusion pressure to form a cable with an inner insulation layer; (4) dispersing the nitrile rubber in a 25% benzene solution of triphenylphosphine in an amount of 3 to 5 times the mass of the nitrile rubber, stirring until a colloid is formed, adding a 10% acetic acid solution in an amount of 0.3 to 0.5 times the mass of the nitrile rubber, heating the mixture to 70 to 80° C. in a water bath, adding hydrogen peroxide in an amount of 0.1 to 0.18 times the mass of the nitrile rubber at a rate of 15 to 20 drops / min, reacting for 1 to 2 hours, transferring the mixture to a reactor, adding rhodium chloride in an amount of 0.05 to 0.08 times the mass of the nitrile rubber, and conducting a hydrogenation reaction under a hydrogen atmosphere. After the reaction is completed, condensing the mixture with anhydrous ethanol, placing the mixture in a vacuum drying oven, and drying the mixture at 60 to 80° C. for 1.5 hours, thereby obtaining epoxy hydrogenated nitrile rubber; (5) dispersing the epoxy hydrogenated nitrile rubber in a 25% triphenylphosphine benzene solution having a mass fraction of 3 to 5 times the mass of the epoxy hydrogenated nitrile rubber, adding 0.2 to 0.3 times the mass of the epoxy hydrogenated nitrile rubber, heating to 80 to 90°C, standing and keeping the reaction for 0.5 to 1 hour, raising the temperature to 120 to 130°C, continuing the reaction for 20 to 30 minutes, condensing with anhydrous ethanol, placing in a vacuum drying oven, and drying at 60 to 80°C for 1.5 hours to obtain amide nitrile rubber; (6) Mix amide nitrile rubber, montmorillonite, polyamide and phosphite in a mass ratio of 40:10:8:0.2 to 45:15:12:0.3 and place them in a heating extruder, heat them to a molten state, and continuously extrude them onto a cable with an inner insulation layer under the action of a forming mold and extrusion pressure to produce an acid-resistant cable.

2. The method for preparing an acid-resistant cable according to claim 1, characterized in that: In the above step (2), the process of oxidizing carbon black is as follows: the carbon black is mixed with 98% nitric acid which is 6 times the mass of the carbon black, stirred at room temperature and 800-1200 rpm for 30 min, heated in an oil bath to 150-180° C., kept warm for 6-8 h, cooled to room temperature, filtered and washed with deionized water until the washing liquid is neutral, and finally dried in a drying oven at 75° C. for 3 h.

3. The method for preparing an acid-resistant cable according to claim 1, characterized in that: In the above step (3): the thickness of the inner insulating layer is 0.03-0.05 mm.

4. The method for preparing an acid-resistant cable according to claim 1, characterized in that: In the above step (6): the thickness of the outer insulating layer is 0.06 to 0.1 mm.